PMM-4879 Adding support for defaults-file.

client/channel/channel.go

@@ -277,6 +277,11 @@ func (c *Channel) runReceiver() {
 				ID:      msg.Id,
 				Payload: p.PbmSwitchPitr,
 			}
+		case *agentpb.ServerMessage_ParseDefaultsFile:
+			c.requests <- &ServerRequest{
+				ID:      msg.Id,
+				Payload: p.ParseDefaultsFile,
+			}
 
 		// responses
 		case *agentpb.ServerMessage_Pong:

client/client.go

@@ -55,10 +55,11 @@ const (
 
 // Client represents pmm-agent's connection to nginx/pmm-managed.
 type Client struct {
-	cfg               *config.Config
-	supervisor        supervisor
-	connectionChecker connectionChecker
-	softwareVersioner softwareVersioner
+	cfg                *config.Config
+	supervisor         supervisor
+	connectionChecker  connectionChecker
+	softwareVersioner  softwareVersioner
+	defaultsFileParser defaultsFileParser
 
 	l       *logrus.Entry
 	backoff *backoff.Backoff
@@ -78,16 +79,17 @@ type Client struct {
 // New creates new client.
 //
 // Caller should call Run.
-func New(cfg *config.Config, supervisor supervisor, connectionChecker connectionChecker, sv softwareVersioner) *Client {
+func New(cfg *config.Config, supervisor supervisor, connectionChecker connectionChecker, sv softwareVersioner, dfp defaultsFileParser) *Client {
 	return &Client{
-		cfg:               cfg,
-		supervisor:        supervisor,
-		connectionChecker: connectionChecker,
-		softwareVersioner: sv,
-		l:                 logrus.WithField("component", "client"),
-		backoff:           backoff.New(backoffMinDelay, backoffMaxDelay),
-		done:              make(chan struct{}),
-		dialTimeout:       dialTimeout,
+		cfg:                cfg,
+		supervisor:         supervisor,
+		connectionChecker:  connectionChecker,
+		softwareVersioner:  sv,
+		l:                  logrus.WithField("component", "client"),
+		backoff:            backoff.New(backoffMinDelay, backoffMaxDelay),
+		done:               make(chan struct{}),
+		dialTimeout:        dialTimeout,
+		defaultsFileParser: dfp,
 	}
 }
 
@@ -436,6 +438,8 @@ func (c *Client) processChannelRequests(ctx context.Context) {
 				resp.Error = err.Error()
 			}
 			responsePayload = &resp
+		case *agentpb.ParseDefaultsFileRequest:
+			responsePayload = c.defaultsFileParser.ParseDefaultsFile(p)
 		default:
 			c.l.Errorf("Unhandled server request: %v.", req)
 		}

client/client_test.go

@@ -78,7 +78,7 @@ func TestClient(t *testing.T) {
 		ctx, cancel := context.WithCancel(context.Background())
 
 		cfg := &config.Config{}
-		client := New(cfg, nil, nil, nil)
+		client := New(cfg, nil, nil, nil, nil)
 		cancel()
 		err := client.Run(ctx)
 		assert.EqualError(t, err, "missing PMM Server address: context canceled")
@@ -93,7 +93,7 @@ func TestClient(t *testing.T) {
 				Address: "127.0.0.1:1",
 			},
 		}
-		client := New(cfg, nil, nil, nil)
+		client := New(cfg, nil, nil, nil, nil)
 		cancel()
 		err := client.Run(ctx)
 		assert.EqualError(t, err, "missing Agent ID: context canceled")
@@ -110,7 +110,7 @@ func TestClient(t *testing.T) {
 				Address: "127.0.0.1:1",
 			},
 		}
-		client := New(cfg, nil, nil, nil)
+		client := New(cfg, nil, nil, nil, nil)
 		err := client.Run(ctx)
 		assert.EqualError(t, err, "failed to dial: context deadline exceeded")
 	})
@@ -156,7 +156,7 @@ func TestClient(t *testing.T) {
 			s.On("Changes").Return(make(<-chan *agentpb.StateChangedRequest))
 			s.On("QANRequests").Return(make(<-chan *agentpb.QANCollectRequest))
 
-			client := New(cfg, &s, nil, nil)
+			client := New(cfg, &s, nil, nil, nil)
 			err := client.Run(context.Background())
 			assert.NoError(t, err)
 			assert.Equal(t, serverMD, client.GetServerConnectMetadata())
@@ -184,7 +184,7 @@ func TestClient(t *testing.T) {
 				},
 			}
 
-			client := New(cfg, nil, nil, nil)
+			client := New(cfg, nil, nil, nil, nil)
 			client.dialTimeout = 100 * time.Millisecond
 			err := client.Run(ctx)
 			assert.EqualError(t, err, "failed to get server metadata: rpc error: code = Canceled desc = context canceled", "%+v", err)
@@ -212,7 +212,7 @@ func TestGetActionTimeout(t *testing.T) {
 	for _, tc := range testCases {
 		tc := tc
 		t.Run(prototext.Format(tc.req), func(t *testing.T) {
-			client := New(nil, nil, nil, nil)
+			client := New(nil, nil, nil, nil, nil)
 			actual := client.getActionTimeout(tc.req)
 			assert.Equal(t, tc.expected, actual)
 		})
@@ -271,7 +271,7 @@ func TestUnexpectedActionType(t *testing.T) {
 	s.On("Changes").Return(make(<-chan *agentpb.StateChangedRequest))
 	s.On("QANRequests").Return(make(<-chan *agentpb.QANCollectRequest))
 
-	client := New(cfg, s, nil, nil)
+	client := New(cfg, s, nil, nil, nil)
 	err := client.Run(context.Background())
 	assert.NoError(t, err)
 	assert.Equal(t, serverMD, client.GetServerConnectMetadata())

client/deps.go

@@ -24,6 +24,7 @@ import (
 
 //go:generate mockery -name=connectionChecker -case=snake -inpkg -testonly
 //go:generate mockery -name=supervisor -case=snake -inpkg -testonly
+//go:generate mockery -name=defaultsFileParser -case=snake -inpkg -testonly
 
 // connectionChecker is a subset of methods of connectionchecker.ConnectionChecker used by this package.
 // We use it instead of real type for testing and to avoid dependency cycle.
@@ -48,3 +49,7 @@ type supervisor interface {
 	// Collector added to use client as Prometheus collector
 	prometheus.Collector
 }
+
+type defaultsFileParser interface {
+	ParseDefaultsFile(req *agentpb.ParseDefaultsFileRequest) *agentpb.ParseDefaultsFileResponse
+}

commands/run.go

@@ -28,6 +28,7 @@ import (
 	"github.com/percona/pmm-agent/client"
 	"github.com/percona/pmm-agent/config"
 	"github.com/percona/pmm-agent/connectionchecker"
+	"github.com/percona/pmm-agent/defaultsfile"
 	"github.com/percona/pmm-agent/versioner"
 )
 
@@ -75,8 +76,9 @@ func run(ctx context.Context, cfg *config.Config, configFilepath string) {
 
 	supervisor := supervisor.NewSupervisor(ctx, &cfg.Paths, &cfg.Ports, &cfg.Server)
 	connectionChecker := connectionchecker.New(&cfg.Paths)
+	defaultsFileParser := defaultsfile.New()
 	v := versioner.New(&versioner.RealExecFunctions{})
-	client := client.New(cfg, supervisor, connectionChecker, v)
+	client := client.New(cfg, supervisor, connectionChecker, v, defaultsFileParser)
 	localServer := agentlocal.NewServer(cfg, supervisor, client, configFilepath)
 
 	go func() {

defaultsfile/defaults_file.go

@@ -0,0 +1,131 @@
+// pmm-agent
+// Copyright 2019 Percona LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//  http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package defaultsfile provides managing of defaults file.
+package defaultsfile
+
+import (
+	"fmt"
+	"os/user"
+	"path/filepath"
+	"strings"
+
+	"github.com/percona/pmm/api/agentpb"
+	"github.com/percona/pmm/api/inventorypb"
+	"github.com/pkg/errors"
+	"gopkg.in/ini.v1"
+)
+
+// Parser is a struct which is responsible for parsing defaults file.
+type Parser struct{}
+
+// New creates new DefaultsFileParser.
+func New() *Parser {
+	return &Parser{}
+}
+
+type defaultsFile struct {
+	username string
+	password string
+	host     string
+	port     uint32
+	socket   string
+}
+
+// ParseDefaultsFile parses given defaultsFile in request. It returns the database specs.
+func (d *Parser) ParseDefaultsFile(req *agentpb.ParseDefaultsFileRequest) *agentpb.ParseDefaultsFileResponse {
+	var res agentpb.ParseDefaultsFileResponse
+	defaultsFile, err := parseDefaultsFile(req.ConfigPath, req.ServiceType)
+	if err != nil {
+		res.Error = err.Error()
+		return &res
+	}
+
+	res.Username = defaultsFile.username
+	res.Password = defaultsFile.password
+	res.Host = defaultsFile.host
+	res.Port = defaultsFile.port
+	res.Socket = defaultsFile.socket
+
+	return &res
+}
+
+func parseDefaultsFile(configPath string, serviceType inventorypb.ServiceType) (*defaultsFile, error) {
+	if len(configPath) == 0 {
+		return nil, errors.New("configPath for DefaultsFile is empty")
+	}
+
+	switch serviceType {
+	case inventorypb.ServiceType_MYSQL_SERVICE:
+		return parseMySQLDefaultsFile(configPath)
+	case inventorypb.ServiceType_EXTERNAL_SERVICE:
+	case inventorypb.ServiceType_HAPROXY_SERVICE:
+	case inventorypb.ServiceType_MONGODB_SERVICE:
+	case inventorypb.ServiceType_POSTGRESQL_SERVICE:
+	case inventorypb.ServiceType_PROXYSQL_SERVICE:
+	case inventorypb.ServiceType_SERVICE_TYPE_INVALID:
+		return nil, errors.Errorf("unimplemented service type %s", serviceType)
+	}
+
+	return nil, errors.Errorf("unimplemented service type %s", serviceType)
+}
+
+func parseMySQLDefaultsFile(configPath string) (*defaultsFile, error) {
+	configPath, err := expandPath(configPath)
+	if err != nil {
+		return nil, fmt.Errorf("fail to normalize path: %w", err)
+	}
+
+	cfg, err := ini.Load(configPath)
+	if err != nil {
+		return nil, fmt.Errorf("fail to read config file: %w", err)
+	}
+
+	cfgSection := cfg.Section("client")
+	port, _ := cfgSection.Key("port").Uint()
+
+	parsedData := &defaultsFile{
+		username: cfgSection.Key("user").String(),
+		password: cfgSection.Key("password").String(),
+		host:     cfgSection.Key("host").String(),
+		port:     uint32(port),
+		socket:   cfgSection.Key("socket").String(),
+	}
+
+	err = validateDefaultsFileResults(parsedData)
+	if err != nil {
+		return nil, err
+	}
+
+	return parsedData, nil
+}
+
+func validateDefaultsFileResults(data *defaultsFile) error {
+	if data.username == "" && data.password == "" && data.host == "" && data.port == 0 && data.socket == "" {
+		return errors.New("no data found in defaults file")
+	}
+	return nil
+}
+
+func expandPath(path string) (string, error) {
+	if strings.HasPrefix(path, "~/") {
+		usr, err := user.Current()
+		if err != nil {
+			return "", fmt.Errorf("failed to expand path: %w", err)
+		}
+		return filepath.Join(usr.HomeDir, path[2:]), nil
+	}
+	return path, nil
+}